Resistive random-access memory (RRAM or ReRAM) is a type of non-volatile (NV) random-access (RAM) computer memory that works by changing the resistance across a dielectric solid-state material often referred to as a memristor. This technology bears some similarities to conductive-bridging RAM (CBRAM), and phase-change memory (PCM).
Normally, a dielectric material does not conduct electric current. In fact, dielectric substances are employed in capacitors for the specific purpose of preventing the flow of current and maintaining separation of electric charge poles. If a sample of dielectric material is subjected to a high enough voltage, it will suddenly conduct because of a phenomenon called dielectric breakdown. In a conventional dielectric material, breakdown causes permanent damage and failure of the associated component. In a memristor, the dielectric breakdown is temporary and reversible.
In the memristor, a deliberately applied voltage causes the medium to acquire microscopic conductive paths called filaments. The filaments appear as a result of various phenomena such as metal migration or physical defects. Once a filament appears, it can be broken or reversed by the application of a different external voltage. The controlled formation and destruction of filaments in large numbers allows for storage of digital data. Numerous substances have been tested for memristor characteristics, including nickel oxide, titanium dioxide, various electrolytes, semiconductor materials, and even some organic compounds.
Professor Hwang’s invention comes with many advantages. Unlike other electronic fabrics, which are encumbered by wires, the RRAM cloth is unobtrusive and can be worn and washed like ordinary clothing. This cloth also has low production costs and can be produced in large quantities like ordinary fabric.